Can you explain the logic of -2 x -2 = 4 or why "-" x " -" = + ??
By cliff19id
@cliff19id (306)
Indonesia
March 6, 2007 11:44pm CST
i would like to ask a question, if "positive" x "positive" ="positive", i think that it's make sense with example one apple x 2 = two apple, but how can negative x negative become positif.i think that it's not make sense. Do you have the logic ? explain to me with the real case
thank you very much
1 person likes this
3 responses
@shogunly (1397)
• Libya
7 Mar 07
Hi , I always wondered at it myself . Like how 2 imaginary numbers can produce a real number . I think only an expert in Logical algebra can answer this satisfactorily , but I will try my hand at it . First let's take the example of -2 times 2 , obviously the result will be -4 , why ? Because times 2 means "repeated twice" so if we have 2 "-2" s we get -4 . Wait , still not clear .Let's make a parallel to real life .
The positive numbers correspond to anything in real life that can be counted , so 2 could be 2 men , 2 dollars , 2 bananas ,2 cars etc . But what about -2 ? If we answer that (what the minus corresponds to in real life ) we are one step closer to answering your query .
@shogunly (1397)
• Libya
11 Mar 07
An example for negative numbers could be made where you are missing a number of things . For example , let's say we have a person who is in debt for 2 dollars , so his fortune equals = -2 dollars . Not only he has nothing , but if you give him 2 dollars he will STILL have nothing . If you give him 3 dollars then 3 + (-2) = 3-2 =1 , he will have 1 dollar left with him after paying the 2 dollar debt .If we multiply by +2 , for example if we had 2 of that person , the total debt will become -4 . So it makes sense that 2 * -2 = -4 . What about -2 * -2 ???
@RAMPersona (2033)
• Philippines
11 Mar 07
..it is because of the symbol "x" (multiplication). it implies 'to cross'.. from '-' and '-' to '-' and '|' joined.
..just my absurdness?
